On 6/29/23 05:59, Andrew Jones wrote:
On Wed, Jun 28, 2023 at 06:30:24PM -0300, Daniel Henrique Barboza wrote:Next patch will add KVM specific user properties for both MISA and multi-letter extensions. For MISA extensions we want to make use of what is already available in misa_ext_cfgs[] to avoid code repetition. misa_ext_info_arr[] array will hold name and description for each MISA extension that misa_ext_cfgs[] is declaring. We'll then use this new array in KVM code to avoid duplicating strings. There's nothing holding us back from doing the same with multi-letter extensions. For now doing just with MISA extensions is enough. Suggested-by: Andrew Jones <ajo...@ventanamicro.com> Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com> --- target/riscv/cpu.c | 83 ++++++++++++++++++++++++++++++---------------- target/riscv/cpu.h | 7 +++- 2 files changed, 61 insertions(+), 29 deletions(-) diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index 2485e820f8..90dd2078ae 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -1558,33 +1558,57 @@ static void cpu_get_misa_ext_cfg(Object *obj, Visitor *v, const char *name, visit_type_bool(v, name, &value, errp); }-static const RISCVCPUMisaExtConfig misa_ext_cfgs[] = {- {.name = "a", .description = "Atomic instructions", - .misa_bit = RVA, .enabled = true}, - {.name = "c", .description = "Compressed instructions", - .misa_bit = RVC, .enabled = true}, - {.name = "d", .description = "Double-precision float point", - .misa_bit = RVD, .enabled = true}, - {.name = "f", .description = "Single-precision float point", - .misa_bit = RVF, .enabled = true}, - {.name = "i", .description = "Base integer instruction set", - .misa_bit = RVI, .enabled = true}, - {.name = "e", .description = "Base integer instruction set (embedded)", - .misa_bit = RVE, .enabled = false}, - {.name = "m", .description = "Integer multiplication and division", - .misa_bit = RVM, .enabled = true}, - {.name = "s", .description = "Supervisor-level instructions", - .misa_bit = RVS, .enabled = true}, - {.name = "u", .description = "User-level instructions", - .misa_bit = RVU, .enabled = true}, - {.name = "h", .description = "Hypervisor", - .misa_bit = RVH, .enabled = true}, - {.name = "x-j", .description = "Dynamic translated languages", - .misa_bit = RVJ, .enabled = false}, - {.name = "v", .description = "Vector operations", - .misa_bit = RVV, .enabled = false}, - {.name = "g", .description = "General purpose (IMAFD_Zicsr_Zifencei)", - .misa_bit = RVG, .enabled = false}, +typedef struct misa_ext_info { + const char *name; + const char *description; +} MISAExtInfo; + +#define MISA_EXT_INFO(_idx, _propname, _descr) \ + [(_idx - 'A')] = {.name = _propname, .description = _descr}We don't have to give up on passing RV* to this macro. Directly using __builtin_ctz() with a constant should work, i.e. #define MISA_EXT_INFO(_bit, _propname, _descr) \ [__builtin_ctz(_bit)] = {.name = _propname, .description = _descr} and then MISA_EXT_INFO(RVA, "a", "Atomic instructions"), MISA_EXT_INFO(RVD, "d", "Double-precision float point"), ... (We don't need the ctz32() wrapper since we know we'll never input zero to __builtin_ctz().)
I'll give it a try. I'll spare us from having to assign name and descr during runtime (at least for this file). Daniel
+ +static const MISAExtInfo misa_ext_info_arr[] = { + MISA_EXT_INFO('A', "a", "Atomic instructions"), + MISA_EXT_INFO('C', "c", "Compressed instructions"), + MISA_EXT_INFO('D', "d", "Double-precision float point"), + MISA_EXT_INFO('F', "f", "Single-precision float point"), + MISA_EXT_INFO('I', "i", "Base integer instruction set"), + MISA_EXT_INFO('E', "e", "Base integer instruction set (embedded)"), + MISA_EXT_INFO('M', "m", "Integer multiplication and division"), + MISA_EXT_INFO('S', "s", "Supervisor-level instructions"), + MISA_EXT_INFO('U', "u", "User-level instructions"), + MISA_EXT_INFO('H', "h", "Hypervisor"), + MISA_EXT_INFO('J', "x-j", "Dynamic translated languages"), + MISA_EXT_INFO('V', "v", "Vector operations"), + MISA_EXT_INFO('G', "g", "General purpose (IMAFD_Zicsr_Zifencei)"), +}; + +const char *riscv_get_misa_ext_name(uint32_t bit) +{ + return misa_ext_info_arr[ctz32(bit)].name; +} + +const char *riscv_get_misa_ext_descr(uint32_t bit)nit: I'd prefer riscv_get_misa_ext_description() for the name.+{ + return misa_ext_info_arr[ctz32(bit)].description; +} + +#define MISA_CFG(_bit, _enabled) \ + {.misa_bit = _bit, .enabled = _enabled} + +static RISCVCPUMisaExtConfig misa_ext_cfgs[] = { + MISA_CFG(RVA, true), + MISA_CFG(RVC, true), + MISA_CFG(RVD, true), + MISA_CFG(RVF, true), + MISA_CFG(RVI, true), + MISA_CFG(RVE, false), + MISA_CFG(RVM, true), + MISA_CFG(RVS, true), + MISA_CFG(RVU, true), + MISA_CFG(RVH, true), + MISA_CFG(RVJ, false), + MISA_CFG(RVV, false), + MISA_CFG(RVG, false), };static void riscv_cpu_add_misa_properties(Object *cpu_obj)@@ -1592,7 +1616,10 @@ static void riscv_cpu_add_misa_properties(Object *cpu_obj) int i;for (i = 0; i < ARRAY_SIZE(misa_ext_cfgs); i++) {- const RISCVCPUMisaExtConfig *misa_cfg = &misa_ext_cfgs[i]; + RISCVCPUMisaExtConfig *misa_cfg = &misa_ext_cfgs[i]; + + misa_cfg->name = riscv_get_misa_ext_name(misa_cfg->misa_bit); + misa_cfg->description = riscv_get_misa_ext_descr(misa_cfg->misa_bit);This might be necessary for the KVM side, but we should be able to avoid this runtime setting here where the compiler can be certain everything is a constant. We just need the old MISA_CFG() back, slightly tweaked to use __builtin_ctz().object_property_add(cpu_obj, misa_cfg->name, "bool",cpu_get_misa_ext_cfg, diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index cc20ee25a7..acae118b9b 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -41,7 +41,10 @@#define RV(x) ((target_ulong)1 << (x - 'A')) -/* Consider updating misa_ext_cfgs[] when adding new MISA bits here */+/* + * Consider updating misa_ext_info_arr[] and misa_ext_cfgs[] + * when adding new MISA bits here. + */ #define RVI RV('I') #define RVE RV('E') /* E and I are mutually exclusive */ #define RVM RV('M') @@ -56,6 +59,8 @@ #define RVJ RV('J') #define RVG RV('G')+const char *riscv_get_misa_ext_name(uint32_t bit);+const char *riscv_get_misa_ext_descr(uint32_t bit);/* Privileged specification version */enum { -- 2.41.0Thanks, drew